Datashee
t
○Product structure：Silicon monolithic integrated circuit ○This product is not designed protection against radioactive rays
. 1/14 TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・14・001
www.rohm.com
For 2Cell Solar,
Synchronous Switch-Mode Charger IC
BU1840AMUV
●General Description
The BU1840AMUV device provides the best system to
the product charged with 1cell Li-ion battery and 3cell
Nickel-metal-hydride batteries using the 2cell, 3cell, and
4cell solar panel.
It is possible to boost it according to the voltage of 2 cell
solar panel with built-in the function to boost the low
voltage input.
Moreover, the solar battery maximum dissipation can be
drawn out with built-in the peak power track function. It is
possible to select the the switching frequency according
to the terminal SEL.
It is also possible to monitor the charging current by the
I2C interface.
Built in heat reckless driving protection (Thermal
shutdown), decrease voltage protection, and input
current protection for protection function
●Features
Synchronous Switch-Mode Charger for 2C ell Solar
400mA@Battery=3.7V,VIN=1V
MPPT control voltage range：0.7V～1.5V
Charging current completion voltage：
5.0V (hysteresis: 0.075V)
Built in MPPT
Switching frequency (1 60kHz,320kHz)
Charging current monitor by I2C
UVLO-detect Voltage:0.625V
UVLO-release Voltage:0.700V
Thermal Shutdown
24 pin VQFN024V4040 (4.1mm×4.1mm<MAX>)
●T ypical Application Circuit(s)
<For 2 Cells Solar>
●Applications
Solar mobile phone
Solar audio
Solar portable charger
Solar LED illumination
●Package(s) W(Typ.) x D(Typ.) x H(Max.)
VQFN024V4040 4.00mm x 4.00mm x 1.00mm
●Typical Performance characteristics
<Efficiency (for 2 cells solar)>
(VINMON=1.0V, OUTS=3.7V, Pin = 50mW ～ 2W)
VQFN024V4040
70
80
90
100
10 100 1000 10000
Pin [mW ]
Ef f iciency [ %]
SEL=GND
SEL=VIN
Datasheet
Datasheet
. 2/14
BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
●Absolute maximum ratings (Ta=25℃)
Parameter Symbol Ratings Unit Conditions
Maximum applied voltage 1 Vmax1 7.0 V VIO,SDA,SCL,SW1,2,3, ENB
COREVDD,OUTP1,2,OUTPM,OUTS
Maximum applied voltage 2 Vmax2 2.5 V VIN,VINMON,V18,IMON,PCOMP,
SEL,OSC
Power dissipation1 Pd1 560 ｍW 1layer(74.2x74.2mm)boad
(Surface heat radiation copper foil：6.28mm )
Power dissipation2 Pd2 1766 ｍW 4layer(74.2x74.2mm)boad
(1,4layer heat radiation copper foil：6.28mm )
(2,3layer heat radiation copper foil：5500mm )
Operating temperature range Topr -30～+85 ℃
Storage temperature range Tstr -55～+150 ℃
*1 When it is used by more than Ta=25℃, it is reduced by 5.6mW/℃. *1
*2 When it is used by more than Ta=25℃, it is reduced by 17.66mW/℃.
●Operating conditions (Ta=25℃)
Parameter Symbol Ratings Unit Conditions
Power supply voltage range 1 VCC1 0.625～1.98 V VIN terminal voltage
Power supply voltage range 2 VCC2 1.7～5.5 V VIO terminal
●Electrical characteristics (Unless otherwise specified: Ta=25℃, VIN=1.0V)
Parameter Symbol
Rating Unit Conditions
Min. Typ. Max.
MPPT control minimum voltage MPPTL - - 0.7 V VINMON-monitor
MPPT control maximum voltage MPPTH 1.5 - - V VINMON-monitor
MPPT-VIN control voltage resolution PPTVT 12.5 25.0 37.5 mV
UVLO Release Threshold VuvloR 0.6 0.7 0.8 V VIN-rising
UVLO Detect Threshold VuvloD 0.575 0.625 0.675 V VIN-falling
UVLO Hysteresis Vuvlohys 30 80 130 mV
MPPT start up voltage Vst1 2.45 2.6 2.75 V COREVDD-monitor
(hys=0.3V)
Charging current completion voltage Vch2 4.93 5.0 5.07 V OUTS-monitor RISING.
(hysteresis=0.075V)
Circuit current 1 (VIN-CURRENT) ICC1 - - 1.0 mA ENB=1V, SW=VIN
Circuit current 2 (OUTS-CURRENT) ICC2 - - 2 uA ENB=1V, OUTS,P=5.2V,
COREVDD=3.7V
Circuit current 3 (OUTS-CURRENT)
Not-Switching ICC3 - - 4 uA
ENB=0V, OUTS,P=5.2V
COREVDD=3.7V
Nch-SW ON registor Rnsw - 60 - mΩ
Pch-SW ON registor Rpsw - 100 - mΩ
Input over current limiter VIlim 3.0 4.0. 5.0 A
DCDC switching frequency 1
(SEL=VIN) Fosc1 260 320 380 kHz OSC2OUT
DCDC switching frequency 2
(SEL=GND) Fosc2 130 160 190 kHz OSC2OUT
Charging current voltage range VImon 0 40 mV V(OUTPM)-V(OUTS)
Charging current monitor accuracy 1 Imon1 0D 2B 49 Hex V(OUTPM)-V(OUTS)=0mV
Charging current monitor accuracy 2 Imon2 88 A6 BF Hex V(OUTPM)-V(OUTS)=40mV
Logic operating clock Logosc - 30 - kHz C4=100pF
ENB ”H” level voltage Venh 1.1 - - V POWER-OFF
ENB ”L” level voltage Venl 0 - 0.2 V POWER-ON
2
2
2
Datasheet
Datasheet
. 3/14
BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
●Electrical characteristics (Unless otherwise specified: Ta=25℃, VIO=1.8V)
Item Symbol Min. Typ. Max. Unit Conditions
【I2C input (SDA, SCL)】
L level input voltage VIL1 -0.3 - 0.25 ×
VIO V
H level input voltage VIH1 0.75 ×
VIO - VIO
+0.3 V
Hysteresis width Vhys1 0.05 ×
VIO - - V
L level output voltage
(Sink current = 3mA) VOL1 0 - 0.3 V SDA pin
Input current Iin1 -3 - 3 μA Pin voltage=0～VIO
●I2C BUS format
The writing/reading operation is based on the I2C slave standard.
・Slave address A7 A6 A5 A4 A3 A2 A1 R/W
1 1 1 0 0 0 1 1/0
・Bit T ransfer
SCL transfers 1-bit data during H. SCL cannot change
signal of SDA during H at the time of bit transfer. If SDA
changes while SCL is H, START conditions or STOP
conditions will occur and it will be interpreted as a
control signal.
・START and STOP condition
When SDA and SCL are H, data is not transferred on
the I2C- bus. This condition indicates, if SDA changes
from H to L while SCL has been H, it will become START
(S) conditions, and an access start, if SDA changes from
L to H while SCL has been H, it will become STOP (P)
conditions and an access end.
・Acknowledge
It transfers data 8 bits each after the
occurrence of START condition. A
transmitter opens SDA after transfer 8bits
data, and a receiver returns the
acknowledge signal by setting SDA to L.
・Protocol
SDA
SCL
SDA a state of stability：
Data are effective SDA
It can change
SDA
SCL SP
START condition STOP condition
12 89
DATA OUTPUT
BY TRANSMITTER
DATA OUTPUT
BY RECEIVER
acknowledge
not acknowledge
S
START condition clock pulse for
acknowledgement
SCL
A
A
S
P
The mastering side is a transmitter.
The slave side is a receiver.
The slave side is a transmitter.
The mastering side is a receiver. Unacknowledged
A
cknowledge
Stop condition
Start con d ition Sr Repetition start condition
Legend
Datasheet
Datasheet
. 4/14
BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
1. Writing protocol
A register address is transferred by the next 1 byte that transferred the slave address and the write-in command. The
3rd byte writes data in the internal register written in by the 2nd byte, and after 4th byte or, the increment of register
address is carried out automaticall y. However, when a register address turns into the last address, it is set to 00h by
the next transmission. After the transmission end, the increment of the address is carried out.
S
A
A
A
P
register addressslave address
from m aster to slave
from slave to master
R/W=0(write)
DATA
A
D7D6D5D4D3D2D1D0 D7 D6 D5 D4 D3 D2 D1 D0
A
7
A
6
A
5
A
4
A
3
A
2
A
1
A
00
X X X X X X X
*1 *1
DATA
A
=acknowledge(SD
A
LOW )
A
=not acknowledge(SDA HIGH)
S=S TART condition
P=STOP condition
*1: Write Ti ming
register address
increment register address
increment
2. Reading protocol
It reads from the next byte after writing a slave address and R/W bit. The register to read considers as the following
address accessed at the end, and th e d ata of the address that carried out the incr ement is read after it. If an address
turns into the last address, the next byte will read out 00h. After the transmission end, the increment of the addr ess is
carried out.
1 S
A
P
from master to slave
from slav e to maste r
R/W=1(read)
DATA
A
DATAslave address
D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0
regist er add ress
increment
X X X X X X X
A
=acknowledge(SD
A
LOW)
A
=not acknowledge(SDA HIGH)
S=START condition
P=STOP condition
register address
increment
A
3. Multiple reading protocols
After specifying an internal address, it reads by repeated START condition and changing the data transfer direction.
The data of the address that carried out the increment is read after it. If an address turns into the last address, the
next byte will read out 00h. After the transmission end, the increment of the address is carried out.
R/W=0(write) R/W=1(read)
slave address regi ster address slave address
DATA DATA
S
A
A
A
Sr 1
0
A
7
A
6
A
5
A
4
A
3
A
2
A
1
A
0X X X X X X X XXXXXXX
A
=acknowledge(SDA LOW )
A
=not acknowledge(SDA HIGH)
S=START condition
P=STOP condition
from master to slave
from slave to master
register ad dress
increment register address
increment
P
A
D7 D6 D5D4 D3 D2 D1 D0 D7D6D5D4D3D2D1D0
A
Sr=repeated START condition
※ As for reading protocol and multiple reading protocols, please do A(not acknowledge) after doing the final reading
operation. It stops with read when ending by A (acknowledge), and SDA stops in the state of Low when the reading
data of that time is 0. However, this state returns usually when SCL is moved, data is read, and A (not acknowledge) i s
done.
Datasheet
Datasheet
. 5/14
BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
●Electrical Characteristics(Unless otherwise specified, Ta=25 ℃, VIO=1.8V)
Item Symbol Standard-mode Fast-mode
Typ.
Min. Typ. Max. Min. Typ. Max.
【I2C BUS format】
SCL clock frequency fSCL 0 - 100 0 - 400 kHz
LOW period of the SCL clock tLOW 4.7 - - 1.3 - - μs
HIGH period of the SCL clock tHIGH 4.0 - - 0.6 - - μs
Hold time for a repeated START condition tHD;STA 4.0 - - 0.6 - - μs
Set-up time for a repeated START condition t S U;STA 4.7 - - 0.6 - - μs
Data hold time tHD;DAT 0 - 3.45 0 - 0.9 μs
Data set-up time tSU;DAT 250 - - 100 - - ns
Set-up time for STOP condition tSU;STO 4.0 - - 0.6 - - μs
Bus free time between a STOP and START condition tBUF 4.7 - - 1.3 - - μs
●Timing diagram
SDA
S
CL
t SU;DAT
t LOW
S Sr P S
t BUF
t HD;STA
t SU;STA
t HIGH
t HD;STA t HD;DAT t SU;STO
●Register Map
Address Symbol
Name R/W D7 D6 D5 D4 D3 D2 D1 D0
INITIAL Function
00h SFTRST W - - - - - - -
SFT
RST 00h
01h ADCDATA R ADC
DATA7 ADC
DATA6 ADC
DATA5 ADC
DATA4 ADC
DATA3 ADC
DATA2 ADC
DATA1 ADC
DATA0 00h
Please input "0" to "-".
In an empty address, there is a possibility of doing assign to the register for the test.
The access to a register for the t est and an undefined regist er is prohibited.
The I2C control timing an d the internal operat ion of IC timing become asyn chronous relations when reading out data from the
outside.
I hope measures so as not to become a problem on the application as the agreement sequence is compare three times.
Datasheet
Datasheet
. 6/14
BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
●Register Explanation
Address Symbol
Name R/W D7 D6 D5 D4 D3 D2 D1 D0 INITIAL データ内容
00h SFTRST W - - - - - - -
SFT
RST 00h ソフトウェア
リセット制御入力
After initializing this all registers when SFTRST: D0=1 is done in WRITE, the value of this register returns to an initial value, too.
Address Symbol
Name R/W D7 D6 D5 D4 D3 D2 D1 D0 INITIAL データ内容
01h ADCDATA R ADC
DATA7 ADC
DATA6 ADC
DATA5 ADC
DATA4 ADC
DATA3 ADC
DATA2
ADC
DATA
1
ADC
DATA0 00h
D7-D0: ADCDATA7-0
8bitADC data（Initial 00h）
Note）When not charging it (V18< 1.6V & DET4OUT=HI <full charge>), doesn't return t he acknowledge signal.
Bit name Bit Function 0 1
SFTRST D0 RST (All registers are initialized.) Normal Reset
Datasheet
Datasheet
. 7/14
BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
●Block diagram
●Block Operation Characteristics
DET1：The voltage of VINMON is detected. (It has hysteresis characterist ics.)
0.700V-DETECT
0.625V-RELEASE
DET2：The voltage of COREVDD (2.6V) is detected. (It has hysteresis characterist ics.)
2.6V-DETECT
2.3V-RELEASE
DET3：The voltage of V18 is detected. (It has hysteresis characteristics.)
1.6V-DETECT
1.5V-RELEASE
DET4：The voltage of OUTS is detected. (I t has hysteresis characteristics.)
5.0V-DETECT
4.925V-RELEASE
OSC1：It is an oscillator. It operates at the self-excitation boost.
OSC2：It is an oscillator. It operates at MPPT.
SEL= GND：frequency=160kHz
SEL= VIN ：frequency=320kHz
OSC3：It is an oscillator. It uses it for the clock in the MPPT-CONT ROL Block and the A/D Block.
DAC ：It is D/A converter. A standard voltage of MPPT is output.
ADC ：It is A/D converter. The analogue signal amplified in the Current-Sense block is converted into the digital signal.
Current-Sense：The OUTPM-OUTS voltage is amplified.
V18REG：Internal power supply V18 is generated from COREVDD.
Current-limiter：The current that flows from SW to PGND is detect ed.
I2C：It is I2C interface block. VIO is made a power supply.
MPPT-Control：To charge it by the solar bat tery maximum dissipation, it controls.
DCDC
Control
ENB
+
-
VINMON
PCOMP
SWN
PGND1,2,3
SW1,2,3
SWP OUTP1,2
DET4
(5V)
VIN
OUTS
500k
+
-
COREVDD
Current
limiter
AGND1,2
Current
Sense
IMON
SEL
I2C
VIOSDA SCL
OUTPM
DAC
OSC3
OSC
V18
VIN
500k
ADC
DET1
0.7V
OSC2
V18REG
DET2
(2.6V)
DET3
(1.6V)
ADCOUT
OSC3OUT
MMPT
Control
DACOUT
OSC1OUT
DET3OUT
OSC2OUT
(160kHz, 320kHz)
DET4OUT
DET2OUT
VIN
OSC1
Datasheet
Datasheet
. 8/14
BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
●Charging Current Sense Register (R1)
It is necessary to decide the constant of R1 in proportion to the maximum charge current.
Maximum charging current ＝ “Maximum input power” × “Efficiency” ÷ “Voltage of battery”
Maximum
charging
current [mA] R1 [mΩ] Maximum
charging
current [mA] R1 [mΩ]
60 560 350 100
80 470 400 100
100 390 480 82
120 330 580 68
150 220 700 56
200 180 820 47
250 150 1000 39
300 120 1200 33
●Charging Current Data
The current for each 1bit of the charge current data is decided by the f ollowing calculating formula
Charging current＝(Charging current data[Hex]－2B[Hex]) × ”Charg ing current / 1bit”
R1 [mΩ] Charging
current/1bit
[mA] R1 [mΩ] Charging
current/1bit
[mA]
33 9.685 150 2.131
39 8.195 180 1.776
47 6.800 220 1.453
56 5.707 270 1.184
68 4.700 330 0.9685
82 3.898 390 0.8195
100 3.196 470 0.6800
120 2.663 560 0.5707
Datasheet
Datasheet
. 9/14
BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
●Operating Sequence
MPPT Voltage
Boost Stop Self Boost MPPT Operation
Changing Current Monitor
Boost Stop MPPT Operation Boost Stop
DET1OUT
(Inter-node)
OSC1OUT
(Inter-node)
DET2OUT
(Inter-node)
V18
DET3OUT
(Inter-node)
OSC2OUT
(Inter-node)
DACOUT
(Inter-node)
ADCDATA
(I2C-Inter face)
DET4OUT
(Inter-node)
OUTS
COREVDD
Operation
1.6V
5.0V
4.925V
2.6V
0.7V
VIN
0.7V
0.7V
VIN MON
0.7V
MPPT Voltage
MPPT Calculation Voltage
Charging Current Monitor
MPPT Voltage
MPPT Calculation Voltage
MPPT Calculation Voltage
MPPT Voltage
MPPT Calculation Voltage
Note) When MPPT operating, it is calculated of MPP each 158mS. (Logosc=30kHz)
The amount of t he MPP voltage change is 25mV step.
Datasheet
Datasheet
. 10/14
BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
●Pin Layout ●Package Diagram
No. PIN Name Function ESD Diode
High side GND side
1 SCL
I2C Interface clock
input pin VIO AGND
2 SDA
I2C Interface data
input and output pin VIO AGND
3 VINMON VIN monitor pin - AGND
4 IMON - COREVDD AGND
5 OUTS
Charging current
sense pin 1 - AGND
6 AGND1 GND pin COREVDD AGND
7 OUTP1 Output voltage pin - AGND
8 OUTP2 Output voltage pin - AGND
9 SW1 Inductor connect pin - -
10 SW 2 Inductor connect pin - -
11 SW 3 Inductor connect pin - -
12 OUTPM
Charging current
sense pin 2 - AGND
13 PGND1 GND pin COREVDD AGND
14 PGND2 GND pin COREVDD AGND
15 PGND3 GND pin COREVDD AGND
16 COREVDD Internal power supply 1 COREVDD AGND
17 V18 Internal po wer supply 2 V18 AGND
18 SEL
DCDC switching frequenc y
changing pin
SEL = GND ：160kHz
SEL = VIN ：320kHz
VIN AGND
19 VIN Solar battery input pin VIN AGND
20 OSC
Logic frequenc y adjustment
pin V18 AGND
21 PCOMP Phase compensation pin V18 AGND
22 AGND2 GND pin V18 AGND
23 ENB
Chip enable pin
(ON:L、OFF:H) - AGND
24 VIO
Power supply pin
for interface
When I2C Interface is not used,
please connect VIO pin
to COREVDD pin.
VIO AGND
VQFN024V4040VQ
Datasheet
Datasheet
. 11/14
BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
●How to select parts of application
<For 2 Cells Solar> <For 4 Cells Solar>
※1 Please set a optimal value for R1 depe nding on maximum charging current . For details, please see p.8 "Charge Current
Sense Register (R1)".
※2 Recommend ed capacitance value of output (OUTS pin) is equivalent to at least 570uF, it is the total of C7(ceramic
capacitors) and C11(aluminum electrolytic capacitors) or C7(ceramic capacitors) and C11(tantalum capacitors).
When select the ceramic capacitor, it takes some consideration of DC bias effect(s). (Recommended pressure capacity:over
10V) With sensitive application to output ripple voltage, taking measures to reduce ESR(Equivalent Series Resistance) such as
increasing of ceramic capacitor or parallel capacitor.
* On BU1840AMUV, output voltage (OUTS pin voltage) rise up to 5.07V; it is the highest value of the ch arge current
completion voltage. Please insert the charging control IC bet ween BU1840AMUV output and secondary battery as necessary.
* When I2C interface is not in use, please connect VIO pin with COREVDD pin dir ect ly.
* In case of charging of the battery with low voltage (less than 3.0V), There is a probability of the emergence of the pattern
periodically repeating MPPT active/non-active mode and it will cause noise. Please insert SBD between SW pin and COREVDD
pin to reduce such noise as necessary.
Value Maker Parts
R1 ※1 - -
R2 24kΩ - -
R3 10Ω - -
R7 100mΩ - -
C1 200uF - -
C2 0.47uF - -
C3 0.1uF - -
C4 100pF - -
C5 22uF - -
C6 2.2uF - -
C7 100uF
※2 - -
C8 22nF - -
C9 47nF - -
C10 10uF - -
C11 470uF
※2 - -
L1 4.7uH～10uH TOKO D128C
D1* SBD - -
Value Maker Parts
R1 ※1 - -
R2 24kΩ - -
R3 10Ω - -
R4 100kΩ - -
R5 100kΩ - -
R6 1kΩ - -
R7 100mΩ - -
C1 200uF - -
C2 0.47uF - -
C3 0.1uF - -
C4 100pF - -
C5 22uF - -
C6 2.2uF - -
C7 100uF
※2 - -
C8 22nF - -
C9 47nF - -
C10 10uF - -
C11 470uF ※2 - -
L1 4.7uH～10uH TOKO D128C
D1* SBD - -
D2 Zener Di RENESAS HZ2A1
Datasheet
Datasheet
. 12/14
BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
●Notes of board layo ut
BU1840AMUV is switching DCDC converter, so characteristics of noise and etc changing by board layout. Please note the
following respect besides a general board la yout matter when you make PCB.
SEL
V18
COREVDD
PGND3
PGND2
PGND1
SCL
SDA
VINMON
IMON
OUTS
AGND1
Low or High
●About heat loss
In the heat design, please operate it in the following condit ion.
(Please consider the margin etc. because the following temperature is a guarantee temperature.)
1. Surrounding temperat ure Ta must be 85℃ or less.
2. Loss of IC must be permissi ble loss Pd or less.
The allowable dissipation (Pd ) characteristics are described below.
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0 25 50 75 100 125
Temperature (℃)
Power Dissipation : Pd (W)
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0 25 50 75 100 125
Temperature (℃)
Power Dissipation : Pd (W)
4layer(74.2×74.2mm)boad
(1,4layer heat r adiation copper foil：6.28mm2)
(2,3layer heat r adiation copper foil：5500mm2)
1layer(74.2×74.2mm)boad
(Surface heat radiation co pper foil：6.28mm2）
Datasheet
Datasheet
. 13/14
BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
●Caution on use
（1）Absolute Maximum Ratings
An excess in the absolute maximum rating, such as supply voltage, temperature range of operating conditions, etc., can
break down devices, thus making impossible to identify breaking mode such as a short circuit or an open circuit. If any
special mode exceeding t he absolute maxim um ratings is assumed, co nsideration shoul d be given to take ph ysical safet y
measures including the use of fuses, etc.
（2）The power supply and the GND lines
Design PCB pattern to provide low impedance for the wiring between the power supply and the GND lines. Please take
care about interference by common impedance of the wiring pattern when there are two or more power supply and
GND line. For the GND line, please note the separation of the large current rout e and the small signal route including
the external circuit.Furthermore, for all power supply terminals to ICs, mount a capacitor between the power supply and the
GND terminal. At the same time, in order to use an electrolytic capacitor, thoroughly check to be sure the characteristics of
the capacitor to be used present no problem including the occurrence of capacity dropout at a low temperature, thus
determining the constan t.
（3）GND voltage
Make setting of the po tential of the GND termin al so tha t it w ill be maintained a t the minimu m in any operating st ate.
（4）Short circuit between terminals and erroneo us mounting
In order to mount ICs on a set PCB, pay thorough attention to the direction and offset of the ICs. Erroneous mounting can break
down the ICs. Furthermore, if a short circuit occurs due to foreign matters entering between terminals or between the terminal
and the power supply or the GND terminal , the ICs can break d own.
（5）Operation in strong electromagnetic field
Be noted that using ICs in the strong electromagnetic field can malfunction them.
（6）Input terminals
In terms of the construction of IC, parasitic elements are inevitably formed in relation to potential. The operation of the parasitic
element can cause interference with circuit operation, thus resulting in a malfunction and then breakdown of the input terminal.
Therefore, pay thorough attention not to handle the input terminals, such as to apply to the input terminals a voltage lower than
the GND respectively, so that any parasitic element will operate. Furthermore, do not apply a voltage to the input terminals when
no power supply voltage is applied to the IC. In addition, even if the power supply voltage is applied, apply to the input terminals
a voltage low er than the power supply voltage or within the guaranteed value of electrical characteristics.
（7）External ca p acitor
In order to use a ceramic capacitor as the external capacitor, determine the constant with consideration given to a
degradation in the nominal capacitance due to DC bias and changes in the capacitance due to temperature, etc.
（8）Thermal design
Perform thermal design in which there are adequate margins by taking into account the permissible dissipation (Pd) in
actual states of use. Moreover, please use it within the range where output Tr doesn't exceed the rated voltage and ASO.
（9）Rush current
In CMOS IC, when the power supply is turned on rush current might flow momentarily in logical internal irregular state.
Therefore, note drawing the capacity of the power supply coupling, the power supply, and width and drawing the GND
pattern wiring, please.
（10）Test terminal and unused terminal processing
Please process a test terminal and unused terminal according to explanations of the function manual and the application
note, etc. to be unquestionable while real used. Moreover, please inquire of the person in charge of our company about
the terminal without the explanatio n especially.
(11)Content of mat erial
The application notes etc. are the design mat erial to design the application, and no one of t he cont ent securing it. Please decide
the application after it examines enough and it evaluates it including exter nal parts.
Status of this document
The Japanese version of t his document is formal spec ification. A customer may use this translati on version only for a ref erence
to help reading the formal version.
If there are any differences in translation version of this document formal version takes priorit y
Datasheet
Datasheet
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BU1840AMUV
TSZ02201-0Q1Q0AJ00130-1-2
© 2012 ROHM Co., Ltd. All rights reserved. 2.AUG.2012 Rev.001
TSZ22111・15・001
www.rohm.com
●Ordering part number
B U 1 8 4 0 A M U V - E 2
Part No. Package Wrapping、Forming specification
MUV : VQFN024V4040 E2: Reel emboss taping
●Physical Dimension Tape a nd Reel Information
●Marking Diagram(s)
(Unit : mm)
VQFN024V4040
0.08 S
S
16
7
12
19
24
1318
0.4±0.1
0.02+0.03
-
0.02
1PIN MARK
2.4±0.1
C0.2
0.5
4.0±0.1
0.75
2.4±0.1
4.0±0.1
1.0MAX
(0.22)
0.25+0.05
-
0.04
∗
Order quantity needs to be multiple of the minimum quantity.
<Tape and Reel information>
Embossed carrier tapeTape
Quantity
Direction
of feed
The direction is the 1pin of product is at the upper left when you hold
reel on the left hand and you pull out the tape on the right hand
2500pcs
E2
()
Direction of feed
Reel 1pin
VQFN024V4040 (TOP VIEW)
1840A
Part Number Marking
LOT Numbe
r
1PIN MARK
Datasheet
Datasheet
Notice - GE Rev.002
© 2014 ROHM Co., Ltd. All rights reserved.
Notice
Precaution on using ROHM Products
1. Our Products are designed and manufactured for application in ordinary electronic equipments (such as AV equipment,
OA equipment, telecommunication equipment, home electronic appliances, amusement equipment, etc.). If you
intend to use our Products in devices requiring extremely high reliability (such as medical equipment (Note 1), transport
equipment, traffic equipment, aircraft/spacecraft, nuclear power controllers, fuel controllers, car equipment including car
accessories, safety devices, etc.) and whose malfunction or failure may cause loss of human life, bodily injury or
serious damage to property (“Specific Applications”), please consult with the ROHM sales representative in advance.
Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way responsible or liable for any
damages, expenses or losses incurred by you or third parties arising from the use of any ROHM’s Products for Specific
Applications.
(Note1) Medical Equipment Classification of the Specific Applications
JAPAN USA EU CHINA
CLASSⅢ CLASSⅢ CLASSⅡb CLASSⅢ
CLASSⅣ CLASSⅢ
2. ROHM designs and manufactures its Products subject to strict quality control system. However, semiconductor
products can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate
safety measures including but not limited to fail-safe design against the physical injury, damage to any property, which
a failure or malfunction of our Products may cause. The following are examples of safety measures:
[a] Installation of protection circuits or other protective devices to improve system safety
[b] Installation of redundant circuits to reduce the impact of single or multiple circuit failure
3. Our Products are designed and manufactured for use under standard conditions and not under any special or
extraordinary environments or conditions, as exemplified below. Accordingly, ROHM shall not be in any way
responsible or liable for any damages, expenses or losses arising from the use of any ROHM’s Products under any
special or extraordinary environments or conditions. If you intend to use our Products under any special or
extraordinary environments or conditions (as exemplified below), your independent verification and confirmation of
product performance, reliability, etc, prior to use, must be necessary:
[a] Use of our Products in any types of liquid, including water, oils, chemicals, and organic solvents
[b] Use of our Products outdoors or in places where the Products are exposed to direct sunlight or dust
[c] Use of our Products in places where the Products are exposed to sea wind or corrosive gases, including Cl2,
H2S, NH3, SO2, and NO2
[d] Use of our Products in places where the Products are exposed to static electricity or electromagnetic waves
[e] Use of our Products in proximity to heat-producing components, plastic cords, or other flammable items
[f] Sealing or coating our Products with resin or other coating materials
[g] Use of our Products without cleaning residue of flux (even if you use no-clean type fluxes, cleaning residue of
flux is recommended); or Washing our Products by using water or water-soluble cleaning agents for cleaning
residue after soldering
[h] Use of the Products in places subject to dew condensation
4. The Products are not subject to radiation-proof design.
5. Please verify and confirm characteristics of the final or mounted products in using the Products.
6. In particular, if a transient load (a large amount of load applied in a short period of time, such as pulse. is applied,
confirmation of performance characteristics after on-board mounting is strongly recommended. Avoid applying power
exceeding normal rated power; exceeding the power rating under steady-state loading condition may negatively affect
product performance and reliability.
7. De-rate Power Dissipation (Pd) depending on Ambient temperature (Ta). When used in sealed area, confirm the actual
ambient temperature.
8. Confirm that operation temperature is within the specified range described in the product specification.
9. ROHM shall not be in any way responsible or liable for failure induced under deviant condition from what is defined in
this document.
Precaution for Mounting / Circuit board design
1. When a highly active halogenous (chlorine, bromine, etc.) flux is used, the residue of flux may negatively affect product
performance and reliability.
2. In principle, the reflow soldering method must be used; if flow soldering method is preferred, please consult with the
ROHM representative in advance.
For details, please refer to ROHM Mounting specification
Datasheet
Datasheet
Notice - GE Rev.002
© 2014 ROHM Co., Ltd. All rights reserved.
Precautions Regarding Application Examples and External Circuits
1. If change is made to the constant of an external circuit, please allow a sufficient margin considering variations of the
characteristics of the Products and external components, including transient characteristics, as well as static
characteristics.
2. You agree that application notes, reference designs, and associated data and information contained in this document
are presented only as guidance for Products use. Therefore, in case you use such information, you are solely
responsible for it and you must exercise your own independent verification and judgment in the use of such information
contained in this document. ROHM shall not be in any way responsible or liable for any damages, expenses or losses
incurred by you or third parties arising from the use of such information.
Precaution for Electrostatic
This Product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. Please take proper
caution in your manufacturing process and storage so that voltage exceeding the Products maximum rating will not be
applied to Products. Please take special care under dry condition (e.g. Grounding of human body / equipment / solder iron,
isolation from charged objects, setting of Ionizer, friction prevention and temperature / humidity control).
Precaution for Storage / Transportation
1. Product performance and soldered connections may deteriorate if the Products are stored in the places where:
[a] the Products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2
[b] the temperature or humidity exceeds those recommended by ROHM
[c] the Products are exposed to direct sunshine or condensation
[d] the Products are exposed to high Electrostatic
2. Even under ROHM recommended storage condition, solderability of products out of recommended storage time period
may be degraded. It is strongly recommended to confirm solderability before using Products of which storage time is
exceeding the recommended storage time period.
3. Store / transport cartons in the correct direction, which is indicated on a carton with a symbol. Otherwise bent leads
may occur due to excessive stress applied when dropping of a carton.
4. Use Products within the specified time after opening a humidity barrier bag. Baking is required before using Products of
which storage time is exceeding the recommended storage time period.
Precaution for Product Label
QR code printed on ROHM Products label is for ROHM’s internal use only.
Precaution for Disposition
When disposing Products please dispose them properly using an authorized industry waste company.
Precaution for Foreign Exchange and Foreign Trade act
Since our Products might fall under controlled goods prescribed by the applicable foreign exchange and foreign trade act,
please consult with ROHM representative in case of export.
Precaution Regarding Intellectual Property Rights
1. All information and data including but not limited to application example contained in this document is for reference
only. ROHM does not warrant that foregoing information or data will not infringe any intellectual property rights or any
other rights of any third party regarding such information or data. ROHM shall not be in any way responsible or liable
for infringement of any intellectual property rights or other damages arising from use of such information or data.:
2. No license, expressly or implied, is granted hereby under any intellectual property rights or other rights of ROHM or any
third parties with respect to the information contained in this document.
Other Precaution
1. This document may not be reprinted or reproduced, in whole or in part, without prior written consent of ROHM.
2. The Products may not be disassembled, converted, modified, reproduced or otherwise changed without prior written
consent of ROHM.
3. In no event shall you use in any way whatsoever the Products and the related technical information contained in the
Products or this document for any military purposes, including but not limited to, the development of mass-destruction
weapons.
4. The proper names of companies or products described in this document are trademarks or registered trademarks of
ROHM, its affiliated companies or third parties.
DatasheetDatasheet
Notice – WE Rev.001
© 2014 ROHM Co., Ltd. All rights reserved.
General Precaution
1. Before you use our Pro ducts, you are requested to care fully read this document and fully understand its contents.
ROHM shall n ot be in an y way responsible or liabl e for fa ilure, malfunction or acci dent arising from the use of a ny
ROHM’s Products against warning, caution or note contained in this document.
2. All information contained in this docume nt is current as of the issuing date and subj ect to change without any prior
notice. Before purchasing or using ROHM’s Products, please confirm the la test information with a ROHM sale s
representative.
3. The information contained in this doc ument is provi ded on an “as is” basis and ROHM does not warrant that all
information contained in this document is accurate an d/or error-free. ROHM shall not be in an y way responsible or
liable for an y damages, expenses or losses incurred b y you or third parties resulting from inaccuracy or errors of or
concerning such information.
